Folly is a noun that means "foolish or crazy behavior." It would be folly to spend all night playing video games when you have a difficult exam the next day.

Folly comes from the Old French word folie meaning "madness, stupidity." It can describe the silly or nonsensical things you do, like the folly of trying to rush across town in the middle of a snowstorm. Or it can describe the trait that makes people act that way: the folly of an inexperienced driver who doesn't know you can't speed on snow-covered roads. Can you see the word fool in folly? Not a coincidence.

Definitions of folly
  1. noun
    the trait of acting stupidly or rashly
    synonyms: foolishness, unwiseness
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    wisdom, wiseness
    the trait of utilizing knowledge and experience with common sense and insight
    indiscretion, injudiciousness
    the trait of being injudicious
    absurdity, fatuity, fatuousness, silliness
    a ludicrous folly
    the quality of being asinine; stupidity combined with stubbornness
    type of:
    a distinguishing feature of your personal nature
  2. noun
    the quality of being rash and foolish
    “trying to drive through a blizzard is the height of folly
    synonyms: craziness, foolishness, madness
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    type of:
    a poor ability to understand or to profit from experience
  3. noun
    foolish or senseless behavior
    synonyms: craziness, foolery, indulgence, lunacy, tomfoolery
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    meshugaas, mishegaas, mishegoss
    (Yiddish) craziness; senseless behavior or activity
    buffoonery, clowning, frivolity, harlequinade, japery, prank
    acting like a clown or buffoon
    schtick, schtik, shtick, shtik
    (Yiddish) a prank or piece of clowning
    type of:
    caper, frolic, gambol, play, romp
    gay or light-hearted recreational activity for diversion or amusement
  4. noun
    a stupid mistake
    synonyms: betise, foolishness, imbecility, stupidity
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    type of:
    error, fault, mistake
    a wrong action attributable to bad judgment or ignorance or inattention
Word Family

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